DOS Fn 4409H: IOCTL Is Drive Remote or SUBST
Expects: AX 4409H
BL drive number (0=default, 1=A, 2=B, etc.)
Returns: AX error code if CF is set to CY
DX Bit 12 is 1: Drive is remote (if no error)
Bit 12 is 0: Drive is local and DX=IoctlDriveInfoRec
Info: Obtains information about a drive, including whether or not it is
remote (on the network). For local drives, this returns
additional information including, which IOCTL fns it supports,
and whether the drive is a logical drive created by the Subst
On return, DX bit 12 (DX & 1000H) is 1 if the drive is remote
(i.e., on a network server) and all other bits are 0.
See IoctlDriveInfoRec for a layout of the flags returned in DX
when bit 12 is 0 (i.e., not a remote drive).
Notes: ■ This is the only way to see if a logical drive ID represents a
Subst drive. It also lets you see if a local drive is shared
by others on the network.
See Also: Fn 44H (IOCTL)
Fn 440AH (Is File/Device Remote)